Liner plate



C. L. FISHER Dec. 12, 1967 LINER PLATE 2 Sheets$heet 1 Filed May 27,1965 I NVE N TO R Omsrowml. 55/155 ATTORN EY$ C. L. FISHER Dec. 12, 1967LINER PLATE 2 Sheets Filed May 27, 1965 Sheet 2 TUNNELL NG D RECT ON x f1 TUNNELLING DIRECTION INVENTOR Cme/sro uee L. Hal/2,

ATTO R N EYS BY M2 42,

United States Patent 3,357,194 LINER PLATE Christopher L. Fisher,Winnipeg, Manitoba, Canada, as-

siguor to Armco Steel Corporation, Middletown, Ohio, a corporation of()lzio Filed May 27, 1965, Ser. No. 459,306 6 Claims. (Cl. 61-45)ABSTRACT OF THE DISCLOSURE Prefabricated ring and lagging liner platefor lining tunnels, caissons, and the like.

In constructing tunnels, arches or the like, a suitable opening isexcavated and as excavation proceeds, the interior must provide supportin order to prevent caveins, and carry the weight bearing on the tunnel.The most common practice of supporting a tunnel is called in the art thering and lagging method, in which a plurality of structural supports(known as rings) are placed at certain intervals with lagging orcovering material spanning the spaces therebetween. The rings may bewooden beams or, in more recent constructions, steel structural members.The lagging can then be any suitable material such as wood, light steelplates, or the like.

Inasmuch as all the above elements must be positioned and secured inplace from the inside of the tunnel, the art has developed various typesof tunnel liner plate having either two or four inwardly extendingflanges provided with bolt holes. In both types of liner plate, theflanges are formed along the longitudinal edges of the sheet so thatwhen a plurality of liner plates are secured together to form a ring,the flanges will form a circumferential seam. In such a construction,the flange serves as the ring, while the other portion of the linerplate serves as what might be called the lagging.

Tunnel liner plates of this construction are in many casesunsatisfactory because the flanges make it impossible to compactly storeor transport the plates. It has also been found in actual practice thatsuch plates can often be difficult to install both because ofdifiiculties in aligning bolt holes in the flanges and because of theproblem of dirt or other material getting caught between adjacentflanges.

From the manufacturers standpoint, it is desirable to provide as muchstrength as possible with as little steel as possible, for obviousreasons. In the prior art liner plates noted above, the formation of theflanges causes certain manufacturing problems as well as increasing thequantity of material necessary to cover a given area.

Accordingly, it is an object of this invention to provide an improvedliner plate which requires less weight of material in relation tostrength to cover a given area, and hence is cheaper to both manufactureand sell.

A further object of the invention is the provision of a tunnel linerplate which is easier to produce from the standpoint of manufacturingoperations involved.

Still a further object of the invention is to provide a tunnel linerplate which is more easily installed by a workman from within. 7

And still another object of the invention is the provision of a tunnelliner plate which is in fact stronger for a given amount of materialthan any liner plate heretofore available.

The study of soil-structure interaction which indicates that the weightof material carried by the tunnel can be borne by the composite actionbetween the tunnel liner and the soil surrounding it, has permitted useof much thinner, lighter material than was previously thought possible.However, this composite action is not available during the constructionof a tunnel when the liner is sur- 3,357,194 Patented Dec. 12, 1967rounded by an irregular void space. In a typical construction, thesevoids are eventually filled by the process known as grouting, inwhich ahardenable slurry is pumped through the wall of the tunnel liner to fillthe space thereabout. But, before this grouting operation takes place,the advantage of the composite action of the soil-structure interactionis not available and in some cases it may be necessary to provideadditional support until the grouting operation is completed.

It is, therefore, still another object of the invention to provide atunnel liner :plate which permits the easy installation of additionalsupports if needed. The additional supports used in conjunction with thetunnel liner plate of this invention are readily removable after thegrouting operation has been completed if this is desirable.

It is still another object of the invention to provide a more flexibletunnel lining system. That is,'one in which a contractor can choosebetween various sizes-(thicknesses) of material with various structuralsupporting members to meet his particular needs. This also means that ifgreater forces are encountered than preliminary calculations predicted,it is possible for the contractor to provide additional support for thestructure already in place.

Various other objects and advantages of this-invention will becomeapparent to the skilled worker in the art as this specificationproceeds. Reference will be made from time to time to the accompanyingdrawings in which:

FIG. lshows a longitudinal cross section through a tunnel constructed inaccordance with the instant invention.

FIG. 2 is a transverse cross sectional view through a single liner plateaccording to this invention.

. FIC 3 is a plan view of a liner plate according to this invention.

FIG. 4 is a transverse cross sectional view on an enlarged scale showingseveral plates according to this invention as joined and a portion ofthe tunnel wall.

FIG. 5 is an exploded view with parts in section showing one way ofsecuring the horizontal seam together.

FIG. 6 is a perspective view of the hook-bolt and wedge-washer forinside fastening of the circumferential seam. 1

FIG. 7 is a cross sectional view showing the use of the above elementsto form a circumferential seam.

Ring and lagging thinking generated the idea that concentrating allbolts (horizontal and circumferential) near the circumferential seamswould give a stronger ring effect when the plates were assembled. A flatsection with or without bolts between these circumferential seams couldbe considered the lagging or covering portion.

Briefly considered, therefore, the present invention-contemplates atunnel liner plate which is generally rectangular in plan view andarcuately curved along its longitudinal axis. In transverse crosssection, the liner plate of this invention includes a generally flatportion, while the longitudinal edges, as will be described hereinafter,are designed to-concentrate the bolts in a circumferential seam, andwithout using inwardly extend ing flanges.

Referring now in more detail to the drawings, FIG. 1 shows a tunnel inthe process of being constructed. The direction of tunneling isindicated by the arrow. The walls of the tunnel have been indicated at10 and the liner plate of this invention installed inside have beengenerally indicated at 11. As will be seen in the righthand portion ofthe figure, the space 12 between the exterior surface of the liner plate11 and the tunnel wall 10 has been filled with grout so that the fulladvantages of soil-structure interaction may be realized. In theleft-hand portion of this figure, the grouting has not yet beenperformed and, accordingly, an additional tem- 3 3 porary structuralsupport shown generally at 13 has been utilizedi As generally indicatedabove, these additional supports may be removed after the grouting hasbeen completed if it is felt that such additional support is notnecessary.

Turning now to FIG. 2, the transverse cross section of the liner plate11 will be described in more detail. As will be apparent from examiningthe drawing, the plate includes a substantially flat central portion 14with the corrugations 15 and 16 located on each side of it. It will benoted that the portion 14 has a very slight crown. This is simply tofacilitate forming the arcuate curve of the plate and performs nostructural function. The outer free edges-of the corrugations 15 and 16terminate, respectively, in the fastening flanges 17 and 18.

The transverse cross section will be so designed that the liner platewill have a neutral axis indicated by the line 19. It will be observedthat the flat central portion 14 is spaced on one side of the neutralaxis, that the neutral axis passes through both the corrugations 15 and16, and that the flange 18 is spaced inside the neutral axis while theflange 17 is spaced outside the neutral axis. As will become apparenthereinafter, the spacing of these flanges with respect to the neutralaxis is a very important facet of this invention. Throughout theremainder of this specification, the word inside or outside will be usedto refer to the inside and outside of the liner as it is placed inposition in the tunnel. Similarly, the phrase leading edge flange ortrailing edge flange will be used with reference to the tunnelingdirection. The tunneling direction has been indicated by the arrow inthis figure and it will be seen that the leading edge flange 17 isdisposed outside the neutral axis, while the trailing edge flange 18 isdisposed inside the neutral axis.

FIG. 3 shows the liner plate of this invention in plan view. It will benoted that the leading edge flange 17 is provided with a plurality ofsubstantially round holes 20 while the trailing edge flange 18 isprovided with a plurality of elongated or slotted holes 21. When aplurality of plates are placed in overlapping edge to edge relationship,theholes along the leading and trailing edges will form acircumferential seam.

Still referring to FIG. 3, it Will be seen that each of the corrugations15 and 16 includes a pair of longitudinally aligned bolt holes 22-22near each transverse edge. By referring briefly back to FIG. 2, it willbe seen that the holes 22-22 are located in that portion of thecorrugation 15 or 16 which is disposed inside the neutral axis of thecross section of the plate. The joint effected by the holes 22-22 ineffect form the horizontal seam of the tunnel liner, but it will beobserved that these bolts are in effect concentrated closely adjacentthose bolts which form the circumferential seam. As indicated earlier,this concentration of bolts in the circumferential seam provides astronger ring eifect when the plates are assembled.

Referring at this time to FIGS. 6 and 7, one method of effecting thecircumferential seam will be described. As explained earlier, it isnecessary that the f-astenings be applied from the inside of the linerstructure. To this end, it has been found desirable to utilize the bolt24 having the off center head 25 at its upper end, and the wedge- Washerhaving the base portion 26 and the upstanding portion 27. The innersurface of the portion 27 is cylindric al and substantiallyperpendicular to the base 26, while the outer portion of the Wedge 27 issloped as shown in the figureJReferring to FIG. 7, it will be seen thatthe bolt, wedge-washer assembly is placed through a pair of alignedopenings 21, 20. When the nut 28 is tightened, it will force thewedge-washer into the holes, which in turn will force the head 25 of thebolt into engagement with the fastening flange.

In FIG. 5, one method of effecting the horizontal seam has been shown.This includes the double nut bar 30 with the threaded openings 31 and 32and the spring clip 33. The spring clip 33 may be engaged in a pair ofopenings 22-22 to hold the double nut bar 30 against the outside of theplate with the openings 31 and 32 aligned, respectively, with the boltholes 22-22. When the next adjacent plate is in proper position, thebolts 34 and 35 may be passed through the aligned holes and into theopenings 31 and 32, respectively, to effect the horizontal seam.

FIG. 4 shows in transverse cross section how a plurality of liner plates11 will be joined together. In view of the relative disposition of thefastening flanges 17 and 18, it will be seen that the successive tunnelliner rings nest within each other. That is, a stove pipe constructionis obtained' This has been found in practice to be a great improvementin tunnel liner construction inasmuch as it insures axial alignment ofthe liner plates, and makes it easier for the workman to align andinstall the individual plates. That is, only a rotational correction isnecessary to align the bolt holes.

It will also be recalled that the leading edge flanges 17 is providedwith substantially round bolt holes, while the trailing edge flange isprovided with the elongated bolt holes. There are several reasons forthis construction. In the first place, this insures a firm grip for thehead 25 of the bolt in the round hole 20 which will always be outermost.Secondly, it will be recognized that the endrnost holes 20 will bejoined when two liner plates are placed in end to end relation. The useof round rather than slotted holes will insure the maintaining of anaccurate circumferential dimension at the leading edge of the tunnelliner.

As indicated earlier in this specification, the concentration of boltsand fastening flanges along the circumferential seam can in effect heconsidered a ring, while the portion of the liner plates (the flatsurface 14) can be considered as lagging or covering. It has also beendiscovered that this central, flat portion 14 is very useful as a basefor additional supporting members. By way of example, such additionalsupporting members can be in the form of channels, I-beams, or H-beamsif necessary. These beams would be formed into ring-like structuralmembers which can be removably set up within the tunnel liner. A numberof such structural members are shown in FIGURE 4 at 40. (In FIGURE 1, aslightly different cross sectional structural member was earlierindicated at 13.)

The presence of the corrugations 1S and 16 on opposite sides of thecentral portion 14 serve to keep the structural member 40 from tippingor moving to either side. As indicated before, the structural memberscan be easily set in place when additional strength is required and justas easily removed completely or placed in another location at a latertime. The structural members are also favorably located to take up aminimum of space inside the tunnel.

In some cases, the liner plate of this invention may be made in areversed configuration so that the structural members can be locatedoutside the liner plates. That is, in the embodiment described thus far,the flat central portion 14 of the liner plate is disposed outside theneutral axis of the plate. In the reversed" configuration, the centralportion will be disposed inside the neutral axis of the plate (thecorrugations will of course also be reversed).

It is believed that the foregoing constitutes a full and completedisclosure of the instant invention. While it has been described interms of an exemplary embodiment, no limitations are to be inferredexcept as set forth in the claims that follow.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. A prefabricated ring and lagging liner plate comprising a generallyrectangular sheet of material arcuately curved along its longitudinalaxis, said sheet in transverse cross section having a substantially flatcentral portion, of

substantial width, a corrugation on each side of said central portion,each said corrugation being substantially narrower than said fl'atcentral portion, and a fastening flange on the outer edge of each saidcorrugation, said fastening flanges having diflerent radii of curvatureand being substantially parallel to said flat central portion, saidsheet in transverse cross section also having a neutral axis passingthrough said corrugations.

2. The liner plate claimed in claim 1 wherein said central portion isspaced outside said neutral axis, and wherein one of said fasteningflanges is disposed on one side of said neutral axis and the other ofsaid flanges is disposed on the opposite side of said neutral axis.

3. The liner plate claimed in claim 1 wherein said central portion iscrowned.

4. The liner plate claimed in claim 1 including a plurality ofsubstantially circular bolt holes along the fastening flange of saidsheet having the longer radius of curvature and a plurality of elongatedbolt holes along the other fastening flange of said sheet.

5. The liner plate claimed in claim 1 including bolt holes along thetransverse edges of said sheet, all said bolt holes being located in aportion of said corrugations disposed inside said neutral axis.

6. The liner plate claimed in claim 1 wherein the portion of each saidcorrugation which is disposed inside said neutral axis includes at leasta pair of longitudinally aligned bolt holes near each transverse edge.

References Cited UNITED STATES PATENTS 971,558 10/1910 Porter 138-173 X977,944 12/1910 Feldt 138173 X 2,148,783 2/1939 Spaulding 6145 2,217,29210/ 1940 Proctor 6145 2,536,758 1/1951 Macleod 138-173 X 2,841,2977/1958 Washabaugh 61-45 X DAVID J. WILLIAMOWSKY, Primary Examiner.

2O DONALD L. TAYLOR, Assistant Examiner.

1. A PREFABRICATED RING AND LAGGING LINER PLATE COMPRISING A GENERALLYRECTANGULAR SHEET OF MATERIAL ARCUATELY CURVED ALONG ITS LONGITUDINALAXIS, SAID SHEED IN TRANSVERSE CROSS SECTION HAVING A SUBSTANTIALLY FLATCENTRAL PORTION, OF SUBSTANTIAL WIDTH, A CORRUGATION ON EACH SIDE OFSAID CENTRAL PORTION, EACH SAID CORRUGATION BEING SUBSTANTIALLY NARROWERTHAN SAID FLAT CENTRAL PORTION, AND A FASTENING FLANGE ON THE OUTER EDGEOF EACH SAID CORRUGATION, SAID